Staphylococcus Aureus- How This Bacteria is Evading Our Immune System

Staph aureas or MRSA (Methicillin-Resistant Staph Aureas) is a bacteria responsible for most boils, many skin infections, abscesses, and when in the blood stream can be a dangerous infection. Fortunately we still have oral antibiotics that work although there are more and more resistant strains limiting our options.

20-50% of us are colonized (have the bacteria living in our nasopharynx).

This study (reported in Science November 2013, “Staphylococccus aureas degrades neutrophil extracellular traps to promote immune cell death” ) has determined how this bacteria has evolved to avoid our immune system. Normally our immune system sends neutrophils (white blood cells) that trap the bacteria in NETs (neutrophil extracellular traps). These would typically allow macrophages (cells like pac-man) to attack and destroy the bacteria. They discovered that S. aureus bacteria were converting NETs into 2-deoxyadenosine which is a molecule toxic to macrophages.

There is not yet a clinical application for this information, but this presents a starting point for us to see if there are interventions that can take advantage of this information to allow our immune systems to clear these infections.